@import "compass/css3";
$screen-xs-max:'768px';
$screen-sm-min:'768px';
$screen-sm-max:'992px';
$screen-md-min:'992px';
$screen-md-max:'1200px';
$screen-lg-min:'1200px';

.xx{
  @include border-radius(0.5px);
}
//小于768px
@media (max-width: $screen-xs-max) {

}
//大于768px，小于992px
@media (min-width: $screen-sm-min) and (max-width: $screen-sm-max) {

}
//大于992px，小于1200px
@media (min-width: $screen-md-min) and (max-width: $screen-md-max) {

}
//大于1200px
@media (min-width: $screen-lg-min) {

}
